There are a variety of approaches to sense position with magnetic sensors that can be used in, for example, a torque-sensing apparatus for automotive power steering. Several sensor configurations have been devised that use a single sensing element facing either a moving magnet, or a moving tooth or slot. In the latter case, the sensing element is mounted on a stationary magnet. These sensors use a single, small sensing element, so they are low cost. However, they may not provide the linearity, precision and repeatability necessary in more demanding applications, such as for torque sensing.
A different type of sensor configuration uses a long sensing element positioned on the surface of a magnet. The element faces a moving ferromagnetic strip or target. Long sensing elements, however, are expensive and fragile. Recently, a magnetoresistor sensor array has been proposed as an alternative to other sensing elements. An optimized configuration of such sensor arrays for use in detecting two-dimensional movement of a magnetic target has heretofore not been examined.